Accessible bathtub

ABSTRACT

Bathtubs and methods for making a bathtubs are disclosed. A bathtub may include a shell, a first door, and a second door. The shell defines a bathing well. A portion of the edge of the shell defines a door opening. The first door is coupled to a first side of the door opening. The second door is coupled to a second side of the door opening opposite the first side of the door opening. The first and second doors are movable into a closed position blocking the door opening.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional PatentApplication No. 61/713,371 entitled “BATHTUB WITH INTEGRATED FRAME” andfiled on Oct. 12, 2012 for George Bentley, which is incorporated hereinby reference.

FIELD

This invention relates to bathtubs and more particularly relates tobathtubs that can be used by people with limited mobility.

BACKGROUND

People with limited mobility, such as elderly or disabled people, mayhave difficulty entering a bathtub by stepping over an edge of the tub,or sitting down in the interior of the tub, or bathing well.Accordingly, conventional bathtubs present a risk of slipping andfalling for bathers with limited mobility. Accessible bathtubs reducethis risk by providing a door in the side of the tub, so that a bathercan enter the bathing well without stepping over a high edge, and byproviding a seat for the bather.

One type of accessible bathtub is the walk-in tub, which typicallyincludes an inward-swinging door. Inward-swinging doors tend to preventleaks, as water pressure forces the door into the door opening, for atight seal. However, inward-swinging doors are typically narrow, toclear the seat when opening. Thus, a walk-in tub with an inward-swingingdoor is accessible by walking bathers, but less accessible by wheelchairusers, or other bathers with difficulty walking.

Another type of accessible bathtub is the slide-in tub, which typicallyincludes a large, outward-swinging door. Opening the door to a slide-intub may expose most of the side of the bathing well, including the seat,so that a bather can slide into the tub from a wheelchair. However,slide-in tubs involve more complex sealing mechanisms than walk-in tubs,as water pressure may exert a large outward force on a large,outward-swinging door. Also, slide-in tubs may not fit in existingbathrooms that were not designed with space for opening a large,outward-swinging door.

SUMMARY

Bathtubs and methods for making bathtubs are disclosed. In variousembodiments, a bathtub may include a shell, a first door, and a seconddoor. In one embodiment, the shell defines a bathing well. In a furtherembodiment, a portion of the edge of the shell defines a door opening.In some embodiments, the first door is coupled to a first side of thedoor opening. In further embodiments, the second door is coupled to asecond side of the door opening opposite the first side of the dooropening. In certain embodiments, the first and second doors are movableinto a closed position blocking the door opening.

In one embodiment, the first door is an inward-swinging door and thesecond door is an outward-swinging door. In a further embodiment, a lipfor the first door prevents the first door from opening outward, and alip for the second door prevents the second door from opening inward. Inanother embodiment, the lip for the first door interfaces with the lipfor the second door in the closed position, to seal a junction betweenthe doors.

In one embodiment, the first door provides access to a foot well and thesecond door provides access to a sea. In a certain embodiment, the seatis integral to the shell. In further embodiments, the seat includes afront central portion, front side portions, and a back portion. In oneembodiment, the front central portion extends in an upwardly slopeddirection from the back portion. In a further embodiment, the front sideportions extend in a downwardly sloped direction from the back portion.In some embodiments, a portion of the shell behind the seat extends upfrom the back portion of the seat in a backwardly sloped direction,forming an inclined seat back. In further embodiments, a portion of theshell beneath the seat extends down from the front central portion andfront side portions of the seat in a backwardly sloped direction,forming a foot well with a recess under the seat for a bather's heels.

In one embodiment, first and second latches are operable to secure thefirst and second doors, respectively, in the closed position. In afurther embodiment, in the closed position, the first door interfereswith releasing the second latch, so that the second door is not openableunless the first door is opened.

In another embodiment, a door handle is attached to the second door. Ina further embodiment, the door handle is movable to secure the first andsecond doors in the closed position by securing the first door betweenthe door handle and a lip for the second door.

In one embodiment, a metal frame is disposed beneath the shell. In afurther embodiment, the metal frame includes adjustable legs. In certainembodiments, structural members are bonded to the shell. In someembodiments, at least one of the structural members may be disposedbetween the shell and a layer of fiber-reinforced polymer. In furtherembodiments, at least one of the structural members may be bonded to thelayer of fiber-reinforced polymer. In certain embodiments, thestructural members may include a wood structural member, a foamstructural member, and/or a honeycomb structural member. In someembodiments, the structural members may include one or more panelssupporting the shell.

In another embodiment of a bathtub, a shell defines a bathing well. In afurther embodiment, a portion of the edge of the shell defines a dooropening. In one embodiment, first and second doors are movable into aclosed position blocking the door opening. In a certain embodiment, afirst hinge couples the first door to the door opening. In a furtherembodiment, the first hinge allows the first door to open into thebathing well. In one embodiment, a second hinge couples the second doorto the door opening. In a further embodiment, the second hinge allowsthe second door to open away from the bathing well. In some embodiments,first and second latches are operable to secure the first and seconddoors, respectively, in the closed position.

In a certain embodiment, structural members may be disposed between theshell and a layer of fiber-reinforced polymer. In a further embodiment,the structural members may be bonded to the shell and to the layer offiber-reinforced polymer.

In one embodiment, a method for making a bathtub includes forming ashell. In a certain embodiment, the shell defines a bathing well, and aportion of the edge of the shell defines a door opening. In oneembodiment, the method includes bonding structural members to the shell.In a further embodiment, the method includes coupling a first door tothe door opening using an interior hinge. In a certain embodiment, themethod includes coupling a second door to the door opening using anexterior hinge. In some embodiments, the method includes moving thefirst and second doors into a closed position blocking the door opening.

In a certain embodiment, forming the shell may include applying shellmaterial to a mold. In a further embodiment, forming the shell mayfurther include removing a portion of the mold with the shell.

BRIEF DESCRIPTION OF THE DRAWINGS

In order that the advantages of the invention will be readilyunderstood, a more particular description of the invention brieflydescribed above will be rendered by reference to specific embodimentsthat are illustrated in the appended drawings. Understanding that thesedrawings depict only typical embodiments of the invention and are nottherefore to be considered to be limiting of its scope, the inventionwill be described and explained with additional specificity and detailthrough the use of the accompanying drawings, in which:

FIG. 1 is a perspective view illustrating one embodiment of a shell fora bathtub;

FIG. 2 is a perspective view further illustrating one embodiment of abathtub that includes the shell of FIG. 1;

FIG. 3 is an enlarged view illustrating a portion of the bathtub of FIG.2;

FIG. 4 is a section view illustrating one embodiment of bathtub doors;

FIG. 5 is a perspective view illustrating one embodiment of a doorhandle;

FIG. 6 is a perspective view illustrating one embodiment of a supportstructure for a bathtub; and

FIG. 7 is a schematic block diagram illustrating one embodiment of amethod for making a bathtub.

DETAILED DESCRIPTION

Reference throughout this specification to “one embodiment,” “anembodiment,” or similar language means that a particular feature,structure, or characteristic described in connection with the embodimentis included in at least one embodiment. Thus, appearances of the phrases“in one embodiment,” “in an embodiment,” and similar language throughoutthis specification may, but do not necessarily, all refer to the sameembodiment, but mean “one or more but not all embodiments” unlessexpressly specified otherwise. The terms “including,” “comprising,”“having,” and variations thereof mean “including but not limited to”unless expressly specified otherwise. An enumerated listing of itemsdoes not imply that any or all of the items are mutually exclusiveand/or mutually inclusive, unless expressly specified otherwise. Theterms “a,” “an,” and “the” also refer to “one or more” unless expresslyspecified otherwise.

Furthermore, the described features, structures, or characteristics ofthe invention may be combined in any suitable manner in one or moreembodiments. In the following description, numerous specific details areincluded to provide a thorough understanding of embodiments of theinvention. One skilled in the relevant art will recognize, however, thatthe invention may be practiced without one or more of the specificdetails, or with other methods, components, materials, and so forth. Inother instances, well-known structures, materials, or operations are notshown or described in detail to avoid obscuring aspects of theinvention.

The schematic flow chart diagrams included herein are generally setforth as logical flow chart diagrams. As such, the depicted order andlabeled steps are indicative of one embodiment of the presented method.Other steps and methods may be conceived that are equivalent infunction, logic, or effect to one or more steps, or portions thereof, ofthe illustrated method. Additionally, the format and symbols employedare provided to explain the logical steps of the method and areunderstood not to limit the scope of the method. Although various arrowtypes and line types may be employed in the flow chart diagrams, theyare understood not to limit the scope of the corresponding method.Indeed, some arrows or other connectors may be used to indicate only thelogical flow of the method. For instance, an arrow may indicate awaiting or monitoring period of unspecified duration between enumeratedsteps of the depicted method. Additionally, the order in which aparticular method occurs may or may not strictly adhere to the order ofthe corresponding steps shown.

FIG. 1 depicts one embodiment of a shell 100 for a bathtub. In thedepicted embodiment, the shell 100 defines a bathing well 102 and a dooropening 106. In various embodiments, the shell 100 may or may notinclude additional features shown in the depicted embodiment, such as adeck 104, a seat 110, a seat back 108, a foot well 112, and a heelrecess 114.

In one embodiment, the shell 100 defines a bathing well 102. The bathingwell 102, in various embodiments, may refer to the space in which aperson sits while bathing, which may be filled with water. In bathtubswith doors, the bathing well 102 may refer to the space available forholding water when the doors are closed.

In the depicted embodiment, the edge of the shell 100 defines a deck 104and a door opening 106. As used herein, the edge of the shell 100 refersto an uppermost portion of the shell 100, where water might spill out ofthe bathing well 102 or leak under the doors, rather than to a physicaledge of the material that forms the shell 100. For example, in thedepicted embodiment, the shell 100 is molded with the physical edge ofthe material that forms the shell 100 pointing downward or outward. Thematerial pointing downward in the front of the shell 100 may form all orpart of an apron for the bathtub. However, the door opening 106 is stilldefined by a portion of the edge (or uppermost portion) of the shell100. In various embodiments, a door opening 106 may refer to a space oropening in a side wall of a bathtub that provides a bather with accessinto the bathing well 102. In certain embodiments, a door or doors maybe movable into a closed position blocking the door opening 106, asshown in FIG. 2, to allow the bathtub to be filled.

In one embodiment, the door opening 106 may be configured to accommodatetwo doors, as described below with regard to FIG. 2. However, in anotherembodiment, the shell 100 may include a door opening 106 configured toaccommodate a single door, such as the inward-swinging door of a walk-intub.

The remainder of the edge of the shell 100, other than the portion thatdefines the door opening 106, may form a deck 104. In variousembodiments, the deck 104 may refer to a lip, or perimeter of the tub.In certain embodiments, hardware such as faucets, handles, detachableshowerheads, grab bars, or the like may be mounted to the deck 104. Inother embodiments, hardware may be mounted in other places such as on abathroom wall. The deck 104 may also be useful in some embodiments forstoring soap, shampoo, and/or other bathing supplies. In anotherembodiment, the shell 100 may not include a deck 104. For example, ashell 100 for an undermount tub may be intended for mounting underneatha separate deck, such as a stone or tile surface, or the like, andtherefore may not include a deck 104 formed by the edge of the shell100.

In one embodiment, a bathtub may include a seat 110. In the depictedembodiment, the seat 110 is integral to the shell 100. In anotherembodiment, the seat 110 may not be integral to the shell 100, but maybe removable to provide a deeper bathing well 102 for bathers who do notwish to use a seat 110. An integral seat 110, in various embodiments,may be formed or molded as part of the shell 100. Molding a seat 110into the shell 100 presents fewer surfaces to clean, and prevents theseat 110 from slipping when in use. Using an integral seat 110 alsoallows the seat 110 to include other features, such as a seat heater,hydrotherapy jets, or the like.

In one embodiment, the seat 110 may include a back portion, a frontcentral portion, and front side portions. As used herein, directionalterms such as “front,” “back” up,” “down,” “upper,” “lower,”“horizontal,” “vertical,” “left,” “right,” and the like, when used withreference to the shell 100 or bathtub in general, refer to theperspective of a user facing the door opening 106 from outside the tub.Thus, the door opening is in the front of the shell 100. However,similar directional terms when used with reference to the seat 110 referto the perspective of a bather in the seat 110, so that the bather'slegs extend off the front of the seat 110. These terms are used, whereapplicable, to provide some clarity of description when dealing withrelative relationships. However, these terms are not intended to implyabsolute relationships, positions, and/or orientations. For example,with respect to an object, an “upper” surface can become a “lower”surface simply by turning the object over. Nevertheless, it is still thesame object.

The back portion of the seat 110 may support a seated bather, and may becontoured for comfortable sitting. The front central portion may extendforward in an upwardly sloped direction from the back portion, forming araised area, or hump, that allows a bather to sit comfortably withoutsliding off the edge of the seat 110. The bather's legs may rest in thefront edge portions of the seat 110, which may extend from the backportion in a downwardly sloped direction, allowing water to drain offthe surface of the seat 110. Thus, in one embodiment, the seat 110 maybe in a saddle shape. In another embodiment, however, the seat 110 mayhave a different shape. For example, in a further embodiment, the seatmay 110 may be flat.

In one embodiment, the shell 100 may include a seat back 108. In thedepicted embodiment, a portion of the shell 100 extends up from the backportion of the seat 110 to form the seat back 108. In a certainembodiment, that portion of the shell 100 may extend up from the backportion of the seat 110 in a backwardly sloped direction to form aninclined seat back 108, which allows a bather to lean backwards in thebathtub.

In one embodiment, the shell 100 may form a foot well 112. As usedherein, a foot well 112 may refer to a portion of the bathing well 102in front of the seat 110. Thus a bather positioned on the seat 110 maysoak his or her feet in the foot well 112. In some embodiments, the seat110 and the foot well 112 may define two separate depths for the bathingwell 102, so that the tub is shallower near the seat 110, and deepernear the foot well 112. In a further embodiment, the foot well 112 maybe the lowest part of the bathing well 102, and a drain may be placed inthe foot well 112. In a certain embodiment, the shell 100 may extenddown from the front edge (the front central portion and front sideportions) of the seat 110 to the bottom of the footwell 112. In afurther embodiment, the portion of the shell 100 beneath the seat 110may extend down from the front central portion and front side portionsof the seat 110 in a backwardly sloped direction, forming a foot well112 with a heel recess 114.

In various embodiments, a heel recess 114 may refer to a recess, or anextension of the foot well 112 underneath the seat 110. In someembodiments, a bather's heels may rest in the heel recess 114 under theseat 110. In the depicted embodiment, the heel recess 114 may extendapproximately five inches beneath the seat 110. In other embodiments,the heel recess 114 may extend a greater or lesser distance under theseat 110. In embodiments where the bathtub includes a heel recess 114,bathers may tuck their legs underneath themselves in a seated position.This facilitates additional hydrotherapy options compared to a tubwithout a heel recess 114. For example, a bather may exercise byperforming squatting motions above the seat 110 with his or her feet inthe heel recess 114. The heel recess 114 also may allow aninward-swinging door to clear the bather's feet, even if the thresholdfor the door opening 106 is low. (A low threshold for the door opening106 may allow easy access into or out of the bathtub.)

In various embodiments, the shell 100 may include various other featuresnot shown in FIG. 1, such as a textured non-slip base, arm rests for theseat 110, openings for a drain, an overflow drain, hydrotherapy jets,deck-mounted hardware, or the like. A bathtub including the shell 100may also include various other components and plumbing hardware. Forexample, in one embodiment, a grab bar may be installed in or near thebathing well 102. In another embodiment, the bathtub may be installedwith thermostatic filler valves, preventing cold water shock or hotwater scalding. In a further embodiment, the filler valves and the drainmay have a larger diameter than conventional tubs, promoting fastfilling and draining of the bathtub. For example, the filler valves mayhave a ¾ inch diameter, and the drain may have a 3 inch diameter. In acertain embodiment, a shower system for the bathtub is provided withvalves separate from the filler valves. In another embodiment, thebathtub is provided with plumbing fixtures similar to those used withconventional tubs. For example, standard filler valves may be used witha diverter that diverts water from the fill spout to the shower. Inlight of this disclosure, it is clear that many possible plumbingcomponents and other components may be used with a bathtub that includesthe shell 100.

The shell 100, in various embodiments, may be formed of variousmaterials, using various methods. For example, in one embodiment, theshell 100 may be formed by vacuum-forming a heated acrylic sheet to anegative mold. In a further embodiment, an acrylic shell 100 may bestrengthened by one or more exterior fiberglass layers. In anotherembodiment, the shell 100 may be formed using a fiberglass hand-layup orspray-layup process with a positive mold. In another embodiment, acomposite shell 100 may be formed by resin transfer molding using aclosed mold. In view of this disclosure, many molding and other formingprocesses are clear which may be suitable for forming the shell 100

In certain embodiments, such as where the shell 100 includes a heelrecess 114, a mold for the shell 100 may not be completely convex orconcave (depending on whether a positive or negative mold is in use).Accordingly, a mold for the shell 100 may include at least one removable“knock-off,” so that forming the shell 100 includes applying shellmaterial to the mold, waiting for the material to cure or harden, andremoving the knock-off portion of the mold along with the shell 100. Theknockoff may then be removed from the shell 100 and reattached to themold.

FIG. 2 depicts one embodiment of a bathtub 200 that includes the shell100 of FIG. 1, including the bathing well 102 and door opening 106. Inthe depicted embodiment, the bathtub 200 further includes a first door202 and a second door 204. In various embodiments, the bathtub 200 mayor may not include additional features shown in the depicted embodiment,such as side panels 206, a maintenance panel 208, one or more hinges210, lips 212 for the first door 202 and second door 204, and doorhandles (shown enlarged in FIG. 3).

In one embodiment, the first door 202 is coupled to a first side of thedoor opening, and the second door 204 is coupled to a second side of thedoor opening 106 opposite the first side of the door opening 106. Asdescribed above, the first door 202 and second door 204 are movable intoa closed position blocking the door opening 106. FIG. 2 depicts thebathtub 100 with the doors 202, 204 in the closed position.

In one embodiment, the doors 202, 204 may be formed using the sametechnique as the shell 100, for a consistent surface finish. Forexample, the doors 202, 204 for a fiberglass shell 100 may be made bymolding fiberglass into exterior and interior portions for each door202, 204, then bonding the interior and exterior portions together andsealing the seam against water leaks. Similarly, in another embodiment,vacuum-formed acrylic doors 202, 204, may be used with a vacuum-formedacrylic shell 100. In certain embodiments, however, the doors 202, 204may be made from a different material than the shell 100, or usingdifferent techniques. For example, in one embodiment, the doors 202, 204may be formed by resin transfer molding even if the shell 100 is formedusing a different technique.

In one embodiment, the first door 202 may provide access to the footwell 112, and the second door 204 may provide access to a seat 110.Thus, in the depicted embodiment, the first door 202 may beapproximately as tall as the depth of the bathing well 102 in the footwell 112 area, and approximately as wide as the foot well 112 so that abather may open the first door 202 and walk into the foot well 112 overa low threshold. Also, in the depicted embodiment, the second door 204may be approximately as tall as the depth of the bathing well 102 overthe seat 110, and approximately as wide as the seat 110, so that openingthe second door 204 exposes the edge of the seat 110, allowing a batherto slide onto the seat 110 from a wheelchair or from a similar seatedposition. A bather may open both doors 202, 204 to slide onto the seat110, so that his or her legs can enter the foot well 112 over a lowthreshold instead of over the first door 202. The door opening 106 maybe shaped to accommodate a tall first door 202 and a shorter second door204, so that the tops of both doors 202, 204 are aligned with the deckof the tub 100

In one embodiment, the first door 202 may open by swinging inward,toward or into the bathing well 102. For example, the first door 202 maybe coupled to a first side of the door opening 106 by an interior hinge(not shown), enabling the first door 202 to open into the bathing well102. In a further embodiment, the second door 204 may open by swingingoutward, away from or out of the bathing well 102. For example, thesecond door 204 may be coupled to a second side of the door opening 106by an exterior hinge 210. In various embodiments, the hinges 210 mayinclude hinges 210 of various types, such as stainless steel hinges,flexible plastic hinges, or other types of hinges suitable for allowingthe doors 202, 204 to pivot about the hinges 210. In view of thisdisclosure, it is clear that many types of hinge 210 are suitable.

In another embodiment, the doors 202, 204 may be coupled to the dooropening 106 in a different way. For example, in one embodiment, thedoors 202, 204 may be removably coupled to the door opening 106, andheld in place by fasteners and/or by water pressure when in use. Inanother embodiment, the doors 202, 204 may be slidably coupled to thedoor opening 106.

In the depicted embodiment, the doors 202, 204 are coupled to oppositesides of the door opening 106 and meet in the middle to seal a junctionbetween the first door 202 and the second door 204. In anotherembodiment, the doors 202, 204 may be coupled to the door opening 106 indifferent places.

In general, a bathtub 200 with two doors 202, 204 provides a largeopening for easy walk-in or slide-in access to the bathtub, but, becausea double-door bathtub 200 uses two smaller doors 202, 204 instead of onelarge door, it is more likely to fit in existing bathrooms, which maynot include space for opening a larger door. For example, the seconddoor 204 may be configured to clear a toilet seat when opening outward.In one embodiment, where the first door 202 opens inward and the seconddoor 204 opens outward, the second door 204 does not involve the complexsealing mechanisms typically associated with a large outward-swingingdoor, because the force due to water pressure is smaller on the smallersurface of the second door 204. Thus, water pressure may hold theinward-swinging first door 202 in place, and a simple latch may besufficient to hold the second door 204 in place with a water-tight seal.

In the depicted embodiment, each of the doors 202, 204 includes a lip212 that keeps the door 202, 204 from opening in the wrong direction. Inone embodiment, an outward-facing lip 212 toward the inside of the firstdoor 202 prevents the first door 202 from opening outward. In a similarembodiment, an inward-facing lip 212 toward the outside of the seconddoor 202 may prevent the second door 202 from opening inward. In variousembodiments, seals may be disposed in the lips 212 of the doors 202,204, or in the shell 100 near the door opening 106, so that water doesnot escape the bathing well 102 when the doors 202, 204 are in theclosed position. In one embodiment, the lip 212 for the first door 202may overlap or interface with the lip 212 for the second door 204 whenthe doors 202, 204 are in the closed position, thus sealing the junctionbetween the doors 202, 204.

In various embodiments, the seals may include gaskets molded into thedoors 202, 204 or into the shell 100 near the door opening 106, gasketsdisposed within channels routed into the doors 202, 204 or into theshell 100 near the door opening 106, gaskets bonded to surfaces of thedoors 202, 204, or the shell 100, or the like. In one embodiment, theseals may include double gaskets to comply with InternationalAssociation of Plumbing and Mechanical Officials (IAPMO) standards. Inanother embodiment, the seals may include a single gasket with anoverflow drain in the threshold of the door opening 106, to comply withIAPMO standards. In a certain embodiment, the seals may not comply withIAPMO standards, but may nevertheless create a water-tight junction thatkeeps water in the bathing well 102.

In one embodiment, the bathtub 200 may include side panels 206. Sidepanels 206 may be made of shell material or other material, and mayextend downward from the shell 100 to a bathroom floor, presenting afinished appearance for the bathtub 200. Using separate side panels 206instead of extending the shell 100 to the bathroom floor reduces thecomplexity of the mold for the shell 100. Nevertheless, in anotherembodiment, the shell 100 may extend to the bathroom floor without theuse of side panels 206. In the depicted embodiment, the bathtub 200 isconfigured for installation in a three-wall alcove. Accordingly, theside panels 206 present a finished appearance for an apron, or skirt onthe front side, but the back and other sides are uncovered. In anotherembodiment, the bathtub 200 may be configured for installation as afreestanding tub, or near fewer walls, and may include side panels 206that present a finished appearance on all or some of the tub sides.

In the depicted embodiment, one of the side panels 208 includes amaintenance panel 208. In another embodiment, one of the side panels 206may be a removable maintenance panel 208. One or more maintenance panels208, in various embodiments, may provide access to components under theshell 100. For example, in the depicted embodiment, a motor for air orwater hydrotherapy jets may be placed under the seat 110, and accessedby removing the maintenance panel 208.

FIG. 3 depicts one embodiment of the circled portion of the bathtub 200of FIG. 2, in an enlargement. The enlargement shows portions of thefirst and second doors 202, 204, including the lips 212 of the doors202, 204 interfacing to seal the junction between the doors 202, 204, asdescribed above with regard to FIG. 2. In the depicted embodiment, thebathtub 200 also includes door handles 302, 304. In one embodiment thedoor handle 302 for the first door 202 operates a latch to open thefirst door 202, or to secure the first door 202 in the closed position.In a further embodiment, the door handle 304 for the second door 204operates a latch to open the second door 204, or to secure the seconddoor 204 in the closed position. In the depicted embodiment, the doorhandle 302 for the first door 202 is palm-activated. Using apalm-activated door handle instead 302, instead of a knob or the like,allows arthritic bathers, or other people with limited use of theirhands, to operate the door 202 unassisted. For example, an amputee maybe able to operate the door handle 302 for the first door 202 using anarm without a hand.

A palm-activated door handle 302 is convenient for use in an embodimentwhere the first door 202 opens inward, as water pressure will preventthe door 202 from opening even if the door handle 302 is inadvertentlyactivated. In one embodiment, the door handle 304 for the second door204 may also be palm-activated. However, in certain embodiments, thesecond door 204 may open outward, creating a risk that the second door204 may open before the bathtub 200 is drained and spill significantquantities of water out of the bathtub 200, if the door handle 304 forthe second door 204 is inadvertently activated. In some embodiments, theability to open the second door 204 before the bathtub 200 has drainedmay be useful for emergency access to the bathtub 200. In certainembodiments, however, the door handle 304 for the second door 204 may beconfigured so that the second door 204 is not openable until the bathtub200 has drained enough to open the first door 202. For example, in thedepicted embodiment, the door handle 304 for the second door 204 is alever that moves in the direction of the first door 202 to release alatch for the second door 204. Thus, when the doors 202, 204 are in theclosed position, the first door 202 prevents the lever from moving, thusinterfering with a bather's ability to operate the door handle 304 torelease the latch for the second door 204. Accordingly, the second door204 is not openable unless the first door 202 is opened.

FIG. 4 depicts one embodiment of the doors 202, 204 in cross-section,including door handles 302, 304 as described above with regard to FIG.3. In the depicted embodiment, the bathtub 200 includes first and secondlatches 402, 404 operable to secure the first and second doors 202, 204,respectively, in the closed position. In one embodiment, the latches402, 404 secure the doors 202, 204 in the closed position by extendinginto holes in corresponding strike plates. For example, in the depictedembodiment, the first latch 402 secures the first door 202 in positionby extending into a strike plate in the second door 204. In anotherembodiment, the first latch 402 may extend into a strike plate in theshell 100. Operating the first door handle 302 retracts the first latch402 from the strike plate, allowing the first door 202 to be opened. Inthe depicted embodiment, the second latch 404 similarly secures thesecond door 204 in position by extending into a strike plate in theshell 100, so that operating the second door handle 304 retracts thesecond latch 404, allowing the second door 204 to be opened. The latches402, 404 may be in various other positions in various embodiments. Forexample, in one embodiment, the latches 402, 404 may be disposed in theshell 100, and may extend into strike plates in the doors 202, 204. Inview of this disclosure, it is clear that many arrangements of doors202, 204 and latches 402, 404 are possible.

FIG. 5 depicts one embodiment of a single door handle 500 that may beused with a bathtub, such as the bathtub 200 of FIG. 2, in place of theseparate door handles 302, 304. In one embodiment, the single doorhandle 500 may be attached to the second door 204. In a furtherembodiment, a bather may secure the doors 202, 204 in the closedposition by moving the door handle 500 to secure the first door 202between the door handle 500 and a lip 212 for the second door 204. Forexample, in one embodiment, the single door handle 500 may be a slidingbolt attached to the second door 204. A sliding bolt may be retracted toclose the doors 202, 204, then extended to secure the first door 202against the lip 212 of the second door 204. In various embodiments, thesingle door handle 500 may be a sliding bolt, an eccentric wheel, apivotable handle, or the like.

In the depicted embodiment, the door closer 500 includes a handle 502, apivot point 504, a pressure point 506, and a screw opening 508. In oneembodiment, the pivot point 504 is pivotally attachable to an insideportion of the second door 204near the door opening, and the handle 502extends from the pivot point. In the depicted embodiment, the screwopening 508 may admit a set screw which attaches the door closer 500 atthe pivot point 504 to a pivoting member embedded in, or attached to thesecond door 204. In various other embodiments, other methods may be usedto pivotally attach the door closer 500 to the second door 204. In afurther embodiment, the pressure point 506 is offset from the handle502. In a different embodiment, though, the pressure point 506 is inline with the handle 502.

To seal the doors 202, 204 closed, a bather brings the doors 202, 204into the closed position, then rotates the handle 502 about the pivotpoint 504, bringing the pressure point 506 across the first door 202, sothat it is pressed against the lip 212 of the second door 204. Placingthe pressure point 506 at an offset position from the handle 502, incertain embodiments, prevents the edge of the first door 202 fromhitting a bather's knuckles on the handle 502 as the first door 202 isclosed. In a certain embodiment, the handle 502 may have other featuresfacilitating easy use, such as an enlarged end portion 510 for easygripping, or a narrower gripping portion 512 configured to be positionedapproximately one and one quarter inches from the wall of the bathtub200. A 1¼ inch distance between a handle 502 and the wall is similar tothe distance between commonly available grab bars as installed on awall, and provides a space that is wide enough for people to comfortablygrasp the handle 502, but narrow enough to avoid trapping or injuringpeoples' wrists if their hands slip.

FIG. 6 depicts one embodiment of a support structure 600 for a bathtub,such as the bathtub 200 of FIG. 2. In the depicted embodiment, thesupport structure 600 includes a front support panel 602, a back supportpanel 604, cross supports 606, a pump support 608, and a metal frame610.

In one embodiment, the front support panel 602 and the back supportpanel 604 may support front and back sides of the shell 100,respectively. In another embodiment, the front support panel 602 and theback support panel 604 may be replaced by other supports, such asseparate panels on either side of the door opening 106, verticalsupports, or the like. However, using panels 602, 604 to support thefull length of the shell 100 reduces flexing that can damage the shell100.

In one embodiment, the panels 602, 604 may be configured to fit theshell 100. For example, in the depicted embodiment, the front supportpanel 602 includes a cutout for the door opening 106, and a cutout foraccessing the pump support 608 via a maintenance panel 208. The backsupport panel 604, in the depicted embodiment, also includes a cutoutfor accessing the pump support 608 and a cutout that allows the shell100 to extend past the back support panel 604, to increase the volume ofthe bathing well 102. Thus, in the depicted embodiment, the back supportpanel 604 supports the shell 100 at an intermediate height along theshell 100, so that the bathing well 102 is larger, but the full heightof the shell 100 is less supported. In another embodiment, however, theback support panel 604 may include a level top edge and may support theshell 100 at its full height. However, the top of the bathing well 102will then be narrower by the thickness of the back support panel 604. Infurther embodiments, the support panels 602, 604 may include additionalopenings for hydrotherapy jets, or the like.

In one embodiment, the support panels 602, 604 may be plywood panelswhich extend from the front of the bathtub 200 to the back, along bothsides. Plywood panels 602, 604 support the bathtub 200 inexpensively,but in other embodiments, other materials such as PVC foam core, marinestructural foam, honeycomb panels, resin-enhanced balsa wood, pressuretreated wood, untreated wood, or the like, may also be used for thesupport panels 602, 604.

In one embodiment, the material for the shell 100 may wrap over the edgeof the shell 100, forming a U-shaped pocket for the front and backsupport panels 602, 604. In this embodiment, the thickness the U-shapedpocket is determined by the thickness of the support panels 602, 604.For example, a plywood support panel 602, 604 may have a 23/32 inchthickness, or a ¾ inch nominal thickness, which fits a corresponding ¾inch pocket in the shell 100.

In the depicted embodiment, the support panels 602, 604 are bonded tothe shell 100, and foam is disposed in any gaps between the shell 100and each support panel 602, 604. Foam may provide additional bonding anda rigid structure where the shell 102 meets a support panel 602, 604. Inone embodiment, the foam may be a spray foam sealant. In anotherembodiment, the foam may be a two-part expanding polyurethane foam. Inlight of this disclosure, many types of foam are clearly suitable foruse in gaps between the shell 100 and a support panel 602, 604.

In one embodiment, cross supports 606 may extend transversely beneaththe bathtub 200, joining the front support panel 602 and the backsupport panel 604. The cross supports 606 may support the shell 100underneath the bathing well 102. Thus, in the depicted embodiment, thecross supports 606 are positioned at various heights to support both theseat 110 and the foot well 112. Cross supports 606 may provide rigidityto the shell 100, so that a thin shell 100 for the bathtub 200 may beless likely to spider or crack.

In various embodiments, the bathtub 200 may include structural membersbonded to the shell 100. In certain embodiments, structural members mayinclude members of the support structure 600, such as support panels602, 604, or cross supports 606. In further embodiments, structuralmembers may include additional ribs, panels, or the like, that arebonded to the shell 100, but not included in the depicted supportstructure 600. For example, a side of the shell 100 opposite the seat110 may include a large, mostly vertical surface area, which may flexand crack under repeated use, but which is not supported by many crosssupports 606 due to being largely vertical. Additional ribs or panelsmay therefore be bonded to the shell 100 in some embodiments, to stiffenand support the shell 100 in that region. In certain embodiments, thesupport panels 602, 604, cross supports 606, or other structural membersmay include various materials, such as plywood, pressure treated wood,untreated wood, PVC foam core, marine structural foam or other foam,honeycomb panels, resin-enhanced balsa wood, or the like.

In various embodiments, the structural members may be bonded to theshell 100 in various ways. For example, in one embodiment, thestructural members may be bonded to the shell 100 with a masticadhesive. In another embodiment, the structural members and the shell100 may be bonded together with an epoxy adhesive. In light of thisdisclosure it is clear that in various embodiments, different adhesivesmay be used to bond the structural members to the shell 100, dependingon the materials used for the structural members and the shell 100.Bonding the structural members to the shell 100 creates a sturdy unifiedstructure by comparison to a metal-framed tub where the shell 100 isstrapped to the frame only at certain points.

In one embodiment, at least one of the structural members may bedisposed between the shell 100 and a layer of fiber-reinforced polymer.In various embodiments, a layer of fiber-reinforced polymer may includea polymer matrix reinforced with fibers. In certain embodiments, thepolymer matrix may include epoxy, vinylester, polyester, phenolformaldehyde resin, or the like. In further embodiments, the reinforcingfibers may include glass fibers, carbon fibers, aramid fibers, or thelike. For example, in one embodiment, the shell 100 may be gelcoatedfiberglass, and support members may be positioned on the shell 100, andcoated with additional layers of glass fibers and resin. In anotherembodiment, the shell 100 may be vacuum-formed acrylic, and fiberglasslayers may be used to strengthen the shell 100 and to attach structuralmembers to the shell 100. Although fiberglass is currently aninexpensive and effective fiber-reinforced polymer, otherfiber-reinforced polymers may be used in other embodiments. In certainembodiments, a layer of fiber-reinforced polymer may be one of multiplelayers.

In a further embodiment, structural members disposed between the shell100 and a layer of fiber-reinforced polymer may be bonded to the shell100 and to the layer of fiber-reinforced polymer, forming asandwich-structured composite. Bonding between layers of asandwich-structured composite bathtub 200 may provide a lightweightbathtub 200 that is stronger than it would be if the layers were notbonded together.

In one embodiment, a pump support 608 joins the support panels 602, 604,and provides support for items that may be located under the seat 110.For example, a motor for hydrotherapy jets may be located under the seat110, and supported by the pump support 608. The pump support 608 may bemade out of the same material as the support panels 602, 604, or thecross members 608, or out of various other materials.

In the depicted embodiment, a metal frame 610 is disposed beneath theshell 100, and supports the support panels 602, 604. In the depictedembodiment, the metal frame 610 is rectangular, and supports the edgesof the tub at the front, back and sides, with an open portion in themiddle. In a further embodiment, the metal frame 610 may includeadjustable legs (not shown), which allow an installer to adjust theheight of each corner of the bathtub 200. For example, in oneembodiment, threaded legs may be screwed into or out of openings in themetal frame 610, to adjust the height of each corner. In view of thisdisclosure, it is clear that other embodiments of the metal frame 610and legs are possible using other materials and configurations. Forexample, a non-rectangular bathtub 200 may in include a non-rectangularmetal frame 610.

Adjusting the height of the bathtub 200 corners may be useful if thebathroom floor is not level, or depending on the location of the P-trapfor the bathtub 200. In some embodiments, the P-trap for the tub drainis installed in the bathroom floor on the same side of the bathroom asthe drain opening in the bathtub 200 itself. If the drain opening is onthe same side as the P-trap, a metal frame 610 may be omitted, and thebathtub 200 may be installed directly on the subfloor of the bathroom.However, if the bathtub 200 is to be installed with the drain opening onthe opposite side of the bathtub 200 from the P-trap, a drain line willrun under the bathtub 200, and a support frame 610 may be used to raisethe bathtub 200, to accommodate the drain line.

FIG. 7 is a schematic block diagram illustrating one embodiment of amethod 700 for making a bathtub 200. The method 700 begins with forming702 a shell 100. As described above with regard to FIG. 1, in certainembodiments, the shell 100 may define a bathing well 102, and a portionof the edge of the shell 100 may define a door opening 106. In someembodiments, forming 702 the shell 100 may include applying shellmaterial to a mold, and removing a portion of the mold, such as aknock-off, with the shell. In a further embodiment, the method 700includes bonding 704 structural members to the shell 100. In a certainembodiment, the method 700 includes coupling 706 a first door 202 to thedoor opening 106 using an interior hinge. In a further embodiment, themethod 700 includes coupling 708 a second door 204 to the door opening106 using an exterior hinge 210. In certain embodiment, the method 700ends with moving 710 the first and second doors 202, 204 into a closedposition blocking the door opening 106.

The present invention may be embodied in other specific forms withoutdeparting from its spirit or essential characteristics. The describedembodiments are to be considered in all respects only as illustrativeand not restrictive. The scope of the invention is, therefore, indicatedby the appended claims rather than by the foregoing description. Allchanges which come within the meaning and range of equivalency of theclaims are to be embraced within their scope.

What is claimed is:
 1. A bathtub comprising: a shell defining a bathingwell, a portion of an edge of the shell defining a door opening; a firstdoor coupled to a first side of the door opening; and a second doorcoupled to a second side of the door opening opposite the first side ofthe door opening, the first and second doors movable into a closedposition blocking the door opening.
 2. The bathtub of claim 1, whereinthe first door is an inward-swinging door and the second door is anoutward-swinging door.
 3. The bathtub of claim 2, wherein a lip for thefirst door prevents the first door from opening outward and a lip forthe second door prevents the second door from opening inward.
 4. Thebathtub of claim 3, wherein the lip for the first door interfaces withthe lip for the second door in the closed position to seal a junctionbetween the doors.
 5. The bathtub of claim 1, wherein the first doorprovides access to a foot well and the second door provides access to aseat.
 6. The bathtub of claim 1, further comprising a seat integral tothe shell, the seat comprising a front central portion, front sideportions, and a back portion, the front central portion extending in anupwardly sloped direction from the back portion, and the front sideportions extending in a downwardly sloped direction from the backportion.
 7. The bathtub of claim 6, wherein a portion of the shellbehind the seat extends up from the back portion of the seat in abackwardly sloped direction, forming an inclined seat back.
 8. Thebathtub of claim 6, wherein a portion of the shell beneath the seatextends down from the front central portion and front side portions ofthe seat in a backwardly sloped direction, forming a foot well with arecess under the seat for a bather's heels.
 9. The bathtub of claim 1,further comprising first and second latches operable to secure the firstand second doors, respectively, in the closed position.
 10. The bathtubof claim 9, wherein, in the closed position, the first door interfereswith releasing the second latch, so that the second door is not openableunless the first door is opened.
 11. The bathtub of claim 1, furthercomprising a door handle attached to the second door, the door handlemovable to secure the first and second doors in the closed position bysecuring the first door between the door handle and a lip for the seconddoor.
 12. The bathtub of claim 1, further comprising a metal framedisposed beneath the shell, the metal frame comprising adjustable legs.13. The bathtub of claim 1, further comprising structural members bondedto the shell.
 14. The bathtub of claim 13, wherein at least one of thestructural members is disposed between the shell and a layer offiber-reinforced polymer and bonded to the layer of fiber-reinforcedpolymer.
 15. The bathtub of claim 13, wherein the structural memberscomprise one or more of a wood structural member, a foam structuralmember, and a honeycomb structural member.
 16. The bathtub of claim 13,wherein the structural members comprise one or more panels supportingthe shell.
 17. A bathtub comprising: a shell defining a bathing well, aportion of an edge of the shell defining a door opening; first andsecond doors movable into a closed position blocking the door opening; afirst hinge coupling the first door to the door opening, the first hingeenabling the first door to open into the bathing well; a second hingecoupling the second door to the door opening, the second hinge enablingthe second door to open away from the bathing well; and first and secondlatches operable to secure the first and second doors, respectively, inthe closed position.
 18. The bathtub of claim 17, further comprising oneor more structural members disposed between the shell and a layer offiber-reinforced polymer and bonded to the shell and the layer offiber-reinforced polymer.
 19. A method for making a bathtub, the methodcomprising: forming a shell, the shell defining a bathing well, aportion of an edge of the shell defining a door opening; bondingstructural members to the shell; coupling a first door to the dooropening using an interior hinge; coupling a second door to the dooropening using an exterior hinge; and moving the first and second doorsinto a closed position blocking the door opening.
 20. The method ofclaim 19, wherein forming the shell comprises applying shell material toa mold and removing a portion of the mold with the shell.